1. Field of the Invention
The present invention is related to additives for formulations used for treating seeds, especially water-dispersible paste formulations. More particularly, the present invention relates to the use of an organosilicone in seed treatment compositions, which enhances the even coating of a pesticide and, where a pigment or dye is present, the color intensity on the seeds.
2. Description of Related Art
Seeds have been treated with a wide variety of enhancement chemicals for decades. These treatments serve to differentiate seed, increase the storage life and viability of the seed, and protect them against disease, pests, and the like. See, for example, De Tempe, J., The Fungicide-Treated Seed in the Soil, Chapter 10, pp. 205–230 (Dev. Agric. Managed-For. Ecol.=, 1979, 6) and Maude, R. B. Pestic. Outlook 1(4):16–22 (1990).
Seed coating is a process of applying finely ground solids or liquids containing dissolved or suspended solids to form a more or less continuous layer covering the natural seed coat. Compositions and formulations used for treating seeds and for foliar treatment of plants are well known. In this regard, U.S. Pat. No. 5,328,942 as well as United Kingdom Patent Application GB 2 095 115 A are illustrative.
To reduce costs, many seed-treatment formulators would prefer to be able to use paste formulations instead of conventional, commercially-available liquid formulations, wherein such use of paste formulations results in significant cost savings. The utilization of a paste formulation tends to result in lesser included amounts of water, but a paste formulation tends to disperse slowly. Yet, it is highly desirable that formulations for treatment of seeds as well as formulations for foliar treatment of plants readily and quickly disperse, preferably uniformly, when combined with water. Those skilled in the relevant art know, however, that conventional non-aqueous paste formulations are generally not capable of readily and quickly dispersing. Furthermore, and as those in the relevant art also know full well, the selection of a dispersant or dispersing agent for inclusion in a paste formulation for treatment of seeds or for foliar treatment of plants must be done carefully for several reasons. For example, while a dispersant, in general, may typically be selected for purposes of providing a certain formulation with a number of desired physical properties, some of which are mentioned herein, the presence of a dispersant or dispersing agent in the paste formulation—because of the surface-charge nature of the dispersant or dispersing agent—may undesirably affect the ability of the formulation to adhere to (i.e. “stick to”) a particular seed or plant leaf; and, if the formulation further includes a dye or coloring agent, may undesirably affect the ability of the formulation to uniformly color the seed or leaf that is to be treated.
However, coloring treated seeds is required by law to avoid misconsumption. Currently, both dyes and pigments are used for seed coloring. Owing to the problem of cleaning off the color from equipment, seed treatment manufacturers and growers prefer using pigments to dyes. Basically, the seed treatment formulation should provide uniform coverage, adequate surface adhesion, and biological efficacy. Both pigments and dyes require even coverage and deposition of the formulation and, additionally, the pigments are very expensive. To the extent that additives can be provided that will help in uniformly depositing the formulation and coloring the seed, they will have market value.
It would therefore be desirable to have commercially-available a flowable concentrate formulation that is not only able to disperse readily and quickly, but is also able to adhere strongly to, and uniformly coat, a treated seed. The attendant possibility of a reduction in the amount of pigment needed in the formulation is an added benefit. Put simply, seed-treatment formulators would mandate a uniform coating of “actives” and coloring agent on their seed, wherein the seed-treatment coating neither “dusts” (i.e. neither causes formation of dust or other particles) nor rubs off their seed, neither of which is desirable.
U.S. Pat. No. 4,753,035 discloses the use of crosslinkable silicone materials to coat botanic seeds, seedlings, meristematic tissue and plant embryos for their protection and to promote germination. The crosslinkable silicone materials are coated onto the seeds, seedlings, meristematic tissues or plant embryos and crosslinked to cure them. It is said that the silicone coatings provide antifungal protection, can be used to carry entrapped plant adjuvants to the site of germination, are permeable to water vapor and oxygen, and allow sunlight to pass through to the germinating seed.
U.S. Pat. No. 5,106,649 discloses a method for improving the bulk flow properties of pesticide-treated plant seeds. The seeds are treated with low levels of a polydimethylsiloxane lubricant which is applied either to seeds that have already been treated with a pesticidal substance or to seeds simultaneously with a pesticidal substance. The polydimethylsiloxane lubricant can be applied either by coapplication from separate compositions or by the application of a composition containing both the pesticidal substance and the polydimethylsiloxane lubricant.
U.S. Pat. No. 5,580,544 discloses water-dispersible paste formulations that are used in connection with seed treatment and foliar treatment of plants to provide excellent dust and rub-off control. The paste formulations comprise an active ingredient and a hydrocarbon oil carrier having a boiling point of at least 150° C. The carrier is present in an amount that is effective for reducing dusting off of the plant leaf or seed. The paste formulations further include a surfactant and an effervescent comprising an alkaline carbonate and a solid and weak acid. The surfactant, the alkaline carbonate, and the solid and weak acid are respectively present in an amount that is effective for enabling the paste formulation to readily and quickly be dispersed in water. The paste formulations are especially suitable for containment in water soluble and/or water-dispersible bags or pouches, such use tending to render the active ingredient safer to handle and therefore better for consumers and the environment.
U.K. Patent No. 1,141,796 discloses a method for modifying the rate of germination of the seed of a plant which comprises applying to the outer surface of the seed a coating of an organosilicon compound or mixture of organosilicon compounds selected from organohalosilanes, organopolysiloxanes and mixtures of defined distillable by-produced organosilicon compounds.
The disclosures of the foregoing are incorporated herein by reference in their entirety.
The foregoing desiderata, as well as other features and advantages of our present invention will become more readily apparent to those skilled in the relevant art upon reading the following summary and detailed description of our present invention.